Sellers have pushed asking prices on their homes to a five-year high, but they are facing slightly more competition than they were one year ago.

Data from the website DeptOfNumbers.com, which tracks inventory and listing price information for 54 large metro areas, shows that inventories are up 7% from a year ago.

A few key takeaways:

—It’s now clear that for-sale inventories probably hit bottom last year after sustained declines that began in 2010.

—While the year-on-year increase through April is large compared to the last few years, the increase is coming off of the lowest levels of for-sale homes in at least a decade.

—Yes, there are signs all around that demand has cooled over the past six months, particularly in some of the most volatile housing markets across the U.S. southwest. But the national picture shows that home supplies are still relatively low. The number of homes for sale is still 15% below the level of two years ago.

Home prices began their rebound two years ago due to short supplies of homes for sale and rising demand. Inventories fell as banks liquidated large numbers of foreclosed homes.

Inventories have stayed low for a number of reasons. Millions of homeowners still owe more than their homes are worth, even though values are up by around 11% over the last two years, according to Zillow Inc. Millions more have a little bit of home equity but are unwilling to sell for less than either the price they paid or the price they think their home should be worth. Meanwhile, some homeowners may be less incentivized to move because they locked in a super-low mortgage rate in 2012 or 2013.

Low inventories have given sellers more pricing power, though there are questions over whether sellers may be getting too greedy in the aftermath of last year’s jump in mortgage rates. Median asking prices, while still up by double digits from a year earlier, have seen their pace of increase flatten out at around 11%. For the 54 metro areas tracked, the median asking price stood at $269,020 in April, the highest level since July 2008.

Home prices are expected to rise around 4% this year, according to the latest forecast from analysts at Goldman Sachs. But they note that the greatest risk to that forecast is that low inventory persists, in which case home prices will overshoot their forecast

“If homeowners with negative equity or in a money-losing position choose to wait for further house price growth before listing their homes and moving, and if construction of new homes stays far below normal, inventory on the market will remain low, leading to larger price appreciation than our central forecast suggests,” wrote Hui Shan, a strategist at Goldman.

Follow this data closely over the next few months to see if the pace of asking price gains slows down. This will be a sign that sellers are throwing in the towel after being too aggressive earlier this year. On the other hand, if inventories decline further, then price appreciation could stay elevated.

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